US20220409148A1 - Computer-assisted tomography system - Google Patents

Computer-assisted tomography system Download PDF

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Publication number
US20220409148A1
US20220409148A1 US17/787,630 US202017787630A US2022409148A1 US 20220409148 A1 US20220409148 A1 US 20220409148A1 US 202017787630 A US202017787630 A US 202017787630A US 2022409148 A1 US2022409148 A1 US 2022409148A1
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United States
Prior art keywords
collimator
ray
drive mechanism
directed
patient
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Pending
Application number
US17/787,630
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English (en)
Inventor
Georg Rose
Thomas Hoffman
Mathias Leopold
Oliver Großer
Maciej Pech
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Otto Von Guericke Universitaet Magdeburg
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Otto Von Guericke Universitaet Magdeburg
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Publication of US20220409148A1 publication Critical patent/US20220409148A1/en
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/02Devices for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
    • A61B6/03Computerised tomographs
    • A61B6/032Transmission computed tomography [CT]
    • A61B6/035Mechanical aspects of CT
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/06Diaphragms
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/12Devices for detecting or locating foreign bodies
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/04Positioning of patients; Tiltable beds or the like
    • A61B6/0407Supports, e.g. tables or beds, for the body or parts of the body

Definitions

  • the invention relates to a computed tomography system, also referred to below as a CT system, for computed tomographic examinations and treatments on patients.
  • a CT system is known, for example, from DE 10 2013 2019 676 A1.
  • the X-rays emitted by an X-ray tube of the CT system may, for example, be collimated by apertures.
  • the object of the invention is to further improve such a CT system in respect of functionality.
  • the CT system according to the invention may in this way be improved by an active collimator.
  • an active collimator makes it possible to assist examinations and treatments by means of the CT system by automatic assistance functions, for example automatic alignment of the directed X-ray beam by means of adjustment of the collimator to a desired position.
  • Further assisting functions are also made possible, for example automatic tracking of instruments during interventions on the patient for dose reduction or volume-of-interest imaging, in which a patient's particular body region to be acquired, for example a particular organ, is purposely illuminated during and after rotation of the gantry by automatic alignment of the directed X-ray beam by means of adjustment of the collimator.
  • the collimator is an apparatus with which a directed X-ray beam (also referred to as a working beam) having a particular solid angle is selected from the entire X-radiation emitted by the X-ray source and is transmitted to the patient.
  • the collimator may for example be configured as an adjustable aperture, for example in the form of mutually displaceable plates with openings.
  • the X-ray detector may, for example, be configured as a multirow detector.
  • a multirow detector combines the advantages of imaging with a high dynamic range (contrast resolution) as well as very accurate determination of the Hounsfield values and very short integration times.
  • the X-ray detector may also be configured as a flat detector, which has the advantage of a very high spatial resolution and a large imaging region.
  • the CT system may also comprise a plurality of such X-ray detectors, in which case one X-ray detector or the other may be used as required.
  • One important application field of the invention is the X-ray assisted image-guided intervention on a patient, for example needle placement for biopsy, instrument placement for tumor treatment, surgical operations and catheter-based interventions for the treatment of blood vessels.
  • the selection of the transmitted directed X-ray beam of the X-ray source may be combined with active automated layer and image detail tracking.
  • the electronic control device may, for example, comprise a computer which carries out particular control and/or regulation steps, for example by means of a computer program.
  • the computer may be configured as a commercially available computer, for example as a PC, laptop, notebook, tablet or smartphone, or as a microprocessor, microcontroller or FPGA, or as a combination of such elements.
  • the automatically actuatable drive mechanism is adapted to adjust the collimator in respect of the emission direction of the directed X-ray beam transmitted by the collimator relative to the patient and/or the X-ray detector in at least two spatial directions.
  • the drive mechanism may, for example, be configured for two-dimensional adjustment of the collimator in the X and Z directions, for example with a mechanism similar to an industrial biaxial positioning system.
  • the control device is adapted to determine the position of an object in the region of the patient table and, as a function of the position determined, to adjust the collimator by means of the drive mechanism in such a way that the detected object lies in the region of the directed X-ray beam transmitted by the collimator, in particular at the center of the directed X-ray beam.
  • the object may, for example, be a part of a medical instrument, for example for tumor treatment or catheter-based intervention, or a biopsy needle. In particular, it may be the distal end of such an instrument. In this way, the automatic function by means of the control device ensures that the object, or the instrument, always lies in the imaging region of the CT system.
  • the control device is adapted for automatic tracking of the detected object when the position of the object varies, and to track the collimator by means of the drive mechanism to the varying position in respect of the emission direction of the directed X-ray beam.
  • This allows automatic tracking of the directed X-ray beam with the object, for example the medical instrument. In this way, the user is relieved even more from manual actions.
  • the automatic function of the control device ensures that the object, or the instrument, still lies in the acquisition region of the CT imaging in the event of a position variation.
  • the control device is adapted to determine the position of the object by means of image processing with the aid of the projections and reconstructed 3D datasets obtained by means of the X-ray detector.
  • This has the advantage that no additional sensor elements are needed for the position acquisition, and if applicable the tracking of the object.
  • the projections and reconstructed 3D datasets acquired by means of the CT image acquisition can be used directly.
  • a 3D approach or a 2D approach may in this case be adopted, as will be explained in more detail below with the aid of examples.
  • a multirow detector allows a 3D approach in the detection and tracking of an object in the CT images, that is to say three-dimensional coordinates of the object can be determined automatically from the CT images.
  • control device is adapted to determine the position of the object with the aid of data of an external measuring instrument, which acquires the position of the object.
  • Position acquisition of the object may therefore be carried out either only by the external measuring instrument or additionally by the external measuring instrument, as a supplement to the CT imaging.
  • the control device has access to a dataset which specifies a desired direction profile of the directed X-ray beam, the control device being adapted, by means of the dataset, to adjust the collimator by means of the drive mechanism in such a way that the directed X-ray beam has a direction profile that corresponds to the direction profile of the dataset.
  • a direction profile is in this case intended to mean a beam direction of the directed X-ray beam which varies over time. In this way, a particular predetermined path along which the directed X-ray beam is intended to be moved may be specified by means of automatic control.
  • the direction profile it is possible to specify not only the direction profile but, depending on the embodiment, also the speed of the adjustment and in general the behavior of the variation in the direction of the directed X-ray beam as a function of time. For example, it may be specified that the directed X-ray beam stays for some time in certain directions before it is adjusted to another direction.
  • the CT system comprises a further drive mechanism by which the position of the patient relative to the gantry of the CT system is automatically adjustable, the electronic control device being adapted for automatic actuation of the further drive mechanism.
  • the range of adjustment of the collimator by means of the automatically actuatable drive mechanism is generally limited by the maximum projection area on the detector.
  • the patient's position may be adjustable automatically by means of the further drive mechanism so that a desired position of the patient can be placed in the image acquisition region of the CT system.
  • the further drive mechanism may be adapted to adjust the patient table or at least a supporting region of the patient table relative to the gantry.
  • the drive mechanism and/or the further drive mechanism is configured as an electromechanical, hydraulic or pneumatic drive mechanism or as a combination of such drive mechanisms.
  • the drive mechanism may, for example, comprise an electric motor for moving the collimator or a hydraulically or pneumatically deployed actuating cylinder or a combination of a plurality of such elements. The same applies for the further drive mechanism.
  • control device is additionally adapted to control the X-ray source and to evaluate the signals of the X-ray detector.
  • all necessary data are available in the control device, both in respect of the signals of the X-ray detector and in respect of the current position of the directed X-ray beam from the collimator.
  • additional information may be combined together, which leads to a simplification of the CT imaging and an increase in the quality of the imaging.
  • the CT system comprises at least one display unit for displaying CT images obtained from the signals of the X-ray detector.
  • the CT images generated by the image reconstruction of the computed tomography may therefore be represented on the display unit, for example a screen.
  • FIG. 1 , 2 shows a part of the CT system in a side view in the case of a multirow detector approach
  • FIG. 3 , 4 shows a part of the CT system in a side view in the case of a projection approach
  • FIG. 5 shows a schematic block diagram of the overall CT system.
  • the CT system represented in the figures comprises an X-ray source 1 , for example an X-ray tube, a collimator 3 , an X-ray detector 7 , an automatically actuatable drive mechanism 11 for adjusting the collimator 3 , a further automatically actuatable drive mechanism 12 , an electronic control device 8 , 9 , which may comprise a computer, and a display unit 10 .
  • a patient 16 lies on a patient table (not depicted) of the CT system.
  • the X-ray source 1 emits X-rays in a beam path 2 to the collimator 3 .
  • Part of the X-radiation is shielded by the collimator 3 in such a way that only a directed X-ray beam 4 is transmitted by the collimator 3 to the patient 16 .
  • the X-ray detector 7 On the other side of the patient 3 from the X-ray source 1 , or the collimator 3 , there is the X-ray detector 7 , for example the conventional multirow detector represented in FIGS. 1 and 2 .
  • the collimator 3 can be adjusted in such a way that the emission direction of the directed X-ray beam 4 is varied relative to the patient 16 , or relative to the X-ray detector 7 .
  • FIG. 1 shows a first region 14 of the X-ray detector 7 , in this case lying relatively far to the left, which is irradiated by the directed X-ray beam 4 .
  • the other regions 15 of the X-ray detector 7 are not irradiated by the directed X-ray beam 4 . If the collimator 3 is now adjusted as represented in FIG. 2 , the direction of the directed X-ray beam 4 changes, for example, in such a way that the irradiated region 14 of the X-ray detector 7 now lies further to the right.
  • the irradiated region 14 can be actively tracked.
  • an object 5 for example a medical instrument
  • an object 5 is intended to be moved with image guidance from an arbitrary starting point, at which the object 5 is located in FIG. 1 , to an end point 13 using automatic assistance by the CT system.
  • the directed X-ray beam 4 is intended to be adjusted so that it always follows the position of the object 5 , for example the distal end of the object 5 .
  • the object 5 is purposely tracked by continuous imaging of the distal end of the object 5 to the end point 13 , which is reached in FIG. 2 .
  • FIGS. 3 and 4 show a similar representation to FIGS. 1 and 2 , as well as the same process of tracking the object 5 from a starting point to the end point 13 .
  • a different X-ray detector 7 is used, for example a flat detector.
  • a 2D approach of the instrument guiding may be carried out in FIGS. 3 and 4 .
  • the aim is, in the scope of a (minimally invasive) image-guided intervention, to have the instrument required for the treatment or the organ to be observed constantly located in the image detail.
  • the instrument is in this case guided freehand by the doctor or, for example, by means of a robot.
  • the centering of the patient has been performed by means of a manually controlled forward displacement of the patient table.
  • the invention addresses, for example, the problem of needle imaging in a fluoroscopic 3D image by means of active layer tracking of the collimator 3 on the tube side. This approach offers the advantage that the intervention can be carried out without interruption and manual readjustment of the patient table is not necessary.
  • automatic volume-of-interest imaging is possible, in which a patient's particular body region to be acquired, for example a particular organ, is purposely illuminated during and after rotation of the gantry by automatic alignment of the directed X-ray beam by means of adjustment of the collimator.
  • the detector rows may be driven individually.
  • the beam can be displaced over the entire depth of the collimator by means of changing the coordinates of the tube collimator. In current systems, this may be up to 512 detector rows, which with an exemplary pixel size of 0.5 mm amounts to about 256 mm. This means that with perpendicular guiding of the needle with respect to the collimated layer, the needle can be acquired over as much as 256 mm without having to displace the patient table.
  • the needle path In order to make the image reconstruction possible, it is advantageous to know the needle path beforehand or acquire it during the imaging. As an alternative, it is possible to record an entire projection dataset needed for the image reconstruction completely by rotation with a constant collimator layer. This allows updating as a function of the gantry rotation speed, which for CT systems available on the market is from 0.5 Hz to 5 Hz.
  • the tracking of the collimator may in this case be performed to coordinates from image processing methods or external tracking methods (for example optical, electromagnetic).
  • stepwise automated tracking of the patient table or positioning of the gantry system is advantageous.
  • the layer tracking may therefore be configured as a combination of an active collimator and positioning of the gantry and/or of the patient table.
  • radiographic projections of larger-area volumes are represented instead of individual patient layers. This type of imaging is employed, inter alia, for vascular interventions and tumor treatments.
  • An advantage over the 3D approach is the large-area observation and overview.
  • a disadvantage is that the depth information is not provided.
  • the active collimator system is intended to be used in order to reduce the irradiated area in which an instrument (for example a catheter) is located, and therefore reduce the dose for the patient.
  • FIG. 5 schematically shows the overall CT system. Again shown is the X-ray source 1 with the beam path 2 of the X-rays, which is restricted by the collimator 3 to form the directed X-ray beam 4 .
  • the directed X-ray beam 4 passes through the patient 16 to the X-ray detector 7 .
  • the layers 6 are recorded as projection images and, optionally, subsequently reconstructed to form a 3D dataset.
  • the X-ray detector 7 sends the acquired signals to a processing computer 8 , which is for example adapted for the recording of data, the reconstruction and the image processing.
  • the processing computer 8 forms a part of the electronic control device.
  • the processing computer 8 is connected to a controller 9 , which is adapted to drive the automatically actuatable drive mechanism 11 .
  • the controller 9 receives control signals from the processing computer 8 .
  • the controller 9 controls the drive mechanism 11 according to these control signals, so that the collimator 3 is adjusted in the desired way.
  • the controller 9 may actuate a further automatically actuatable drive mechanism 12 , for example in order to adjust the position of the patient relative to the CT gantry.
  • the patient table may be adjusted by the drive mechanism 12 .
  • the processing computer 8 is furthermore coupled to the display unit 10 .
  • the CT images determined by means of the processing computer 8 can in this way be represented on the display unit 10 .
US17/787,630 2019-12-23 2020-12-16 Computer-assisted tomography system Pending US20220409148A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE102019135782.9A DE102019135782A1 (de) 2019-12-23 2019-12-23 Computertomographie-System
DE102019135782.9 2019-12-23
PCT/EP2020/086516 WO2021130084A1 (de) 2019-12-23 2020-12-16 Computertomographie-system

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US20220409148A1 true US20220409148A1 (en) 2022-12-29

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US (1) US20220409148A1 (de)
EP (1) EP4081124A1 (de)
JP (1) JP2023508915A (de)
DE (1) DE102019135782A1 (de)
WO (1) WO2021130084A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20220244196A1 (en) * 2021-01-29 2022-08-04 Shandong University Fast industrial ct scanning system and method

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6173039B1 (en) * 1998-08-25 2001-01-09 General Electric Company Variable aperture z-axis tracking collimator for computed tomograph system
EP2224852A1 (de) * 2007-12-21 2010-09-08 Koninklijke Philips Electronics N.V. Synchroner interventioneller scanner
US8897413B2 (en) * 2008-05-21 2014-11-25 Koninklijke Philips N.V. Dynamic adjustable source collimation during fly-by scanning
DE102008049695A1 (de) * 2008-09-30 2010-04-01 Siemens Aktiengesellschaft Verfahren zum Betreiben eines Röntgenbildaufnahmesystems sowie Röntgenbildaufnahmesystem
DE102012202498B4 (de) * 2012-02-17 2018-08-09 Siemens Healthcare Gmbh Automatische Positionierung von Kollimatoren
DE102012205245B4 (de) * 2012-03-30 2020-07-23 Siemens Healthcare Gmbh Angiographisches Untersuchungsverfahren eines Patienten zur 3-D-Rotationsangiographie
FR2993447B1 (fr) * 2012-07-17 2014-07-11 Gen Electric Procede et systeme de traitement d'images pour l'affichage 3d d'un organe d'un patient
JP6437194B2 (ja) * 2012-12-21 2018-12-12 キヤノンメディカルシステムズ株式会社 X線診断装置
DE102013019676A1 (de) 2013-11-22 2015-05-28 GM Global Technology Operations LLC (n. d. Ges. d. Staates Delaware) Karosserieanordnung für ein Kraftfahrzeug und Verfahren zur Herstellung einer Karosserieanordnung
US11311267B2 (en) * 2018-01-31 2022-04-26 Siemens Healthcare Gmbh Method of position planning for a recording system of a medical imaging device and medical imaging device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20220244196A1 (en) * 2021-01-29 2022-08-04 Shandong University Fast industrial ct scanning system and method
US11821853B2 (en) * 2021-01-29 2023-11-21 Shandong University Fast industrial CT scanning system and method

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JP2023508915A (ja) 2023-03-06
WO2021130084A1 (de) 2021-07-01
EP4081124A1 (de) 2022-11-02
DE102019135782A1 (de) 2021-06-24

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